[net/dns] Rename SystemHostResolverProc and CallSystemHostResolverProc.

net/dns/host_resolver_proc.h

Index: net/dns/host_resolver_proc.h
diff --git a/net/dns/host_resolver_proc.h b/net/dns/host_resolver_proc.h
index b4fc0faa0e8f45c62961a7bece0612f637f851bf..ee8777f44bf95c24b8244a89ef0a6e1af60c67cb 100644
--- a/net/dns/host_resolver_proc.h
+++ b/net/dns/host_resolver_proc.h
@@ -84,13 +84,28 @@ class NET_EXPORT HostResolverProc
 // |addrlist| with a list of socket addresses. Otherwise returns a
 // network error code, and fills |os_error| with a more specific error if it
 // was non-NULL.
-NET_EXPORT_PRIVATE int SystemHostResolverProc(
+NET_EXPORT_PRIVATE int SystemHostResolverCall(
     const std::string& host,
     AddressFamily address_family,
     HostResolverFlags host_resolver_flags,
     AddressList* addrlist,
     int* os_error);
 
+// Wraps call to SystemHostResolverCall as an instance of HostResolverProc.
+class SystemHostResolverProc : public HostResolverProc {
+ public:
+  SystemHostResolverProc();
+  virtual int Resolve(const std::string& hostname,
+                      AddressFamily address_family,
+                      HostResolverFlags host_resolver_flags,
+                      AddressList* addr_list,
+                      int* os_error) OVERRIDE;
+ protected:
+  virtual ~SystemHostResolverProc();
+
+  DISALLOW_COPY_AND_ASSIGN(SystemHostResolverProc);
+};
+
 }  // namespace net
 
 #endif  // NET_DNS_HOST_RESOLVER_PROC_H_